[JAVA] Add acos, asin, ceil and floor lang.Math builtins

[Andrew Haley]

Roger Sayle writes:
 > 
 > The following patch adds support for implementing the lang.Math functions
 > acos, asin, ceil and floor using GCC's mathematical builtins.  When using
 > -ffast-math this allows acos and asin to be expanded as x87 inline
 > intrinsics on IA-32, and for floor and ceil with constant arguments to
 > be constant folded at compile-time.
 > 
 > The following patch has been tested on i686-pc-linux-gnu with a full
 > bootstrap including java, and tested with a top-level "make -k check"
 > with no new failures.
 > 
 > Ok for mainline?

Looks good.   

Thanks,
Andrew.